Open AccessDust‐induced chemical differentiation in dense regions
Author(s) -
Casu Silvia,
CecchiPestellini Cesare,
Aiello Santi
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2001.04524.x
Subject(s) - extinction (optical mineralogy) , physics , astrophysics , halo , molecular cloud , cosmic dust , range (aeronautics) , thermal , interstellar cloud , astrobiology , astronomy , atmospheric sciences , meteorology , stars , galaxy , optics , materials science , composite material
Dust grains respond to the physical and chemical conditions of the interstellar region in which they are embedded. The interaction produces an extinction curve which depends on the local environment and on the past history of the dust grains. In this work we present a theoretical study of the effects of radial variations of dust extinction properties on gas‐phase chemistry in spherical core–halo clouds. We use observational constraints on the variation range of the extinction curve, and we analyse if the degree of dust environmental processing could be reflected by chemical signatures in the gas‐phase molecular concentrations. The results of this work show that significant variations in the photodestruction rates and in the thermal profile of the cloud might induce chemical patterns otherwise excluded in the standard dense‐cloud chemistry. Some discrepancies between observations and theoretical provisions are discussed in the light of the present results.